Low fare search for ticket changes using married segment indicators

ABSTRACT

Systems and techniques for managing ticket changes are described. for managing changes to a purchased ticket. A married segment indicator associated with first and second married flight segments of the purchased ticket is located. It is determined whether changes to the purchased ticket affect existing bookings of the first and second married flight segments. Based on the determination, a replacement ticket is constructed to include the first and second married flight segments of the purchased ticket utilizing the existing booked inventory; otherwise, a replacement ticket is constructed using current availability information for the first and second married flight segments from the replacement ticket.

CROSS-RELATED APPLICATION

Under 35 U.S.C. 119(e)(1), this application claims the benefit ofprovisional application serial number, 60/806,665, filed Jul. 6, 2006,entitled, “LOW FARE SEARCH FOR TICKET CHANGES.”

TECHNICAL FIELD

This invention relates to computerized travel planning systems, and moreparticularly to managing ticket changes.

BACKGROUND

Travel planning systems are used to produce itineraries and prices byselecting suitable travel units from databases containing geographic,scheduling and pricing information. In the airline industry, fundamentaltravel units include “flights” (sequences of regularly scheduledtakeoffs and landings assigned a common identifier) and “fares” (pricespublished by airlines for travel between two points). The term“itinerary” corresponds to a sequence of flights on particular dates andthe term “pricing solution” corresponds to a combination of fares anditineraries that satisfies a travel request and which can be used toprovide a ticket for transportation. Travel planning systems such asthose offered by various web-sites and computer reservation systemsenables individual consumers and travel agents, alike, to search foravailable faring solutions satisfying a travel query. One such system isthe “QPX” travel planning system by ITA Software®. Aspects of the QPXtravel planning system are described in U.S. Pat. No. 6,275,808 andassigned to the assignee of the present application and incorporatedherein by reference. The faring solutions that are returned to the user(i.e., an individual consumer or travel agent) include all of theinformation required to book and ticket the itinerary directly in acarrier's inventory system or in a computer reservation system (CRS).For booking a trip, QPX enables users to retrieve a wide range of pricesand itineraries of available tickets.

SUMMARY

If a user wishes to make a change to an already purchased ticket,determining pricing solutions for the change is a complex and convolutedprocess that most often yields an extremely large number of possiblepricing solutions; because it is possible to purchase a new ticket anddiscard the existing ticket, the total number of possible solutions to aticket change request is strictly larger than the set of possible newtickets that satisfy the user's request.

The invention provides systems and methods, including computer programproducts, for managing changes to purchased tickets.

In general, in one aspect, the invention features a system including oneor more processors configured to locate a married segment indicatorassociated with first and second married flight segments of thepurchased ticket; determine whether changes to the purchased ticket donot affect existing bookings of the first and second married flightsegments; if the ticket changes do not affect the existing booking atleast one of the first and second married flight segments, construct areplacement ticket including changes to the purchased ticket, thereplacement ticket including the first and second married flightsegments of the purchased ticket utilizing the existing bookedinventory; otherwise, if the ticket changes affect at least one of thefirst and second married flight segments, using current availabilityinformation for the first and second married flight segments from thereplacement ticket.

In general, in another aspect, the invention features a method and acomputer program product for presenting travel information to a user.The method includes locating a married segment indicator associated withfirst and second married flight segments of the purchased ticket;determining whether changes to the purchased ticket do not affectexisting bookings of the first and second married flight segments; ifthe ticket changes do not affect the existing booking at least one ofthe first and second married flight segments, constructing a replacementticket including changes to the purchased ticket, the replacement ticketincluding the first and second married flight segments of the purchasedticket utilizing the existing booked inventory; otherwise, if the ticketchanges affect at least one of the first and second married flightsegments, using current availability information for the first andsecond married flight segments from the replacement ticket.

Embodiments may include one or more of the following. It may bedetermined that the changes affect the existing booking of one of thefirst and second married flight segments of the purchased ticket; and acandidate replacement ticket including the married flight segment may bediscarded. A response to an availability query associated with thereplacement ticket may be received. The response may include a marriedsegment indicator associated with the first and second married flightsegments of the replacement ticket. The married segment indicator mayindicate that the first and second flight segments held in the passengername record of the purchased ticket are to be considered as oneindivisible unit of travel. The changes may affect a destination airportof one of the first and second married flight segment. The first andsecond married flight segments from the purchased ticket may be usedwhen constructing the replacement ticket if the changes do not affectthe first and second married flight segments of the purchased ticket.

One or more of the aspects of the invention may provide one or more ofthe following advantages. Airlines spend less money on travel agents whoperform refunds or reissuing of tickets, and airlines' rules forrefunding or reissuing tickets are enforced more uniformly. An automatedsystem instructs travel agents how to refund or reissue a ticket,reducing costly “debit memos” from the airlines. The end user ispresented with all available options for changing their ticket and, as aresult, can make an informed decision about how to proceed withexchanging the ticket for a refund or a new ticket.

The details of one or more embodiments of the invention are set forth inthe accompanying drawings and the description below. Other features,objects, and advantages of the invention will be apparent from thedescription and drawings, and from the claims.

DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram of a travel planning system;

FIG. 2 is a block diagram of a server for use with the travel planningsystem of FIG. 1;

FIG. 3 is a block diagram of a client for use with the travel planningsystem of FIG. 1;

FIG. 4A is a block diagram of the historical database for use with thetravel planning system of FIG. 1;

FIG. 4B is a flow chart showing a fare reconstruction process performedusing the historical database of FIG. 4A;

FIG. 4C is a flow chart showing a fare rule reconstruction processperformed using the historical database of FIG. 4A;

FIG. 5 is a flow chart showing a server process performed by the serverof FIG. 2;

FIG. 6 is a flow chart showing the ticket reconstruction process of FIG.5 in further detail;

FIG. 7 is a flow chart showing the itinerary determination process ofFIG. 5 in further detail;

FIG. 8 is a flow chart showing the availability determination process ofFIG. 5 in further detail;

FIGS. 9A-9B collectively show a flow chart of the reissue methoddetermination process of FIG. 5 in further detail;

FIGS. 10A-10B collectively show a flow chart of the faring process ofFIG. 5 in further detail; and

FIGS. 11A-11E show different views of the user interface.

DETAILED DESCRIPTION

Referring to FIG. 1, a system 10 for travel planning, particularlyadapted for reuse of issued tickets includes a client system 14 (orother system, e.g., terminal to input data) and a travel planning server12 (server 12) coupled to the client system 14, via a network 22. Theserver 12 includes a search engine 18 that searches for pricingsolutions in response to user queries, and also in conjunction with therefund/reissue logic 19, processes refund/reissue requests for usersthat hold issued tickets. Also included in the travel planning system 10are a historical database 20 and an inventory database 26. While thetravel planning system 10 can process conventional travel relatedqueries from users, the travel planning system 10 also processes userrequested refunds and/or reissued tickets.

The travel planning system 10 can be used with various forms of travelsuch as airline, bus and railroad and is particularly adapted for airtravel. The travel planning system 10 may exist separately as astandalone system or may be implemented as an extension of an existingtravel planning system capable of searching fares for future airlinetravel. An example of such an existing system is the travel planningsystem described in U.S. Pat. No. 6,295,521 filed by Carl G. deMarken etal on Jul. 2, 1998 and incorporated herein by reference, although othertravel planning systems may be used in conjunction with therefund/reissue logic 19.

Details of refund/reissue logic 19 will now be described. A user (e.g.,an individual consumer or a travel agent) at client 14 specifies one ormore existing tickets to consider for reuse and parameters of a new tripin a query. The client 14 sends the query to the server 12 over network22, which can be any local or wide area network or an arrangement suchas the Internet. At the server 12, the search engine 18 and therefund/reissue logic 19 process the user's query to produce a completeset of pricing solutions for the new travel using aspects of the alreadyissued ticket. In determining the pricing solutions, the refund/reissuelogic 19 considers any rules associated with the existing ticket thatspecify conditions under which the existing ticket may be changed orexchanged. The rules are stored in the historical database 20. Thehistorical database 20 is stored in the memory 42 of server 12. Thehistorical database 20 may be built elsewhere from raw data files anddistributed to the server 12 over the network 22. The client 14 receivesthe pricing solutions from the server 12 over the network 22 andpresents the results to the user 16. The user 16 may sort the results byvarious criteria or extract a subset of results that fit the user'scriteria. For example, the user may wish to view only the cheapestoptions, and of these, the user may wish to sort the results based on atime of day, carrier, length of travel, or other criteria. After theuser selects one of the options presented by the client 14, the systembooks the new itinerary directly in a carrier's inventory system or in acomputer reservation system (CRS) and reissues a ticket for the newtravel.

The travel planning system 10 includes an historical database 20 thatstores industry-standard information pertaining to travel (e.g.,airline, bus, railroad, etc.). For example, the inventory database 20can store the Airline Tariff Publishing Company database of publishedairline fares and their associated rules, routings and other provisions,the so-called ATPCO database. The system also includes an inventorydatabase 26, which holds an inventory of current seat availabilityinformation for a particular carrier and so forth. The inventory andhistorical databases 26 and 20 may each actually be composed of severaldatabases and may be stored locally within the server 12 or remotely onexternal servers connected to the network 22. In addition, the inventorydatabase 26 and the historical database 20 may be managed together. Theinventory database 26 includes inventory (i.e., seat availability) anduses a combination of live polling, caching, and availabilityprediction/computation.

Structure of an Airline Ticket

The system shown in FIG. 1 is described in the context of airline travelfor determining pricing solutions for changes to an already issuedairline ticket. In general, an airline ticket includes two parts. Afirst part is a reservation also referred to as a passenger name record(PNR), and a second is a ticket document, which can be either a physicalor electronic document.

A PNR is an entry in one or more airlines' reservation databases thatholds information such as the passengers' names, the flight segments ofa trip, and which inventory (“booking code”) has been reserved on eachsegment of the trip. A PNR may also include information, such as ticketnumbers, frequent flyer numbers, etc. and be assigned a uniqueidentification number or alphanumeric string called a “record locator.”

A ticket document on the other hand, is a contractual document thatentitles the holder to travel according to the PNR associated with theticket. For example, a ticket document may show proof of a promise bythe issuing agency to pay for the travel, or that the travel has alreadybeen paid for by the holder. A ticket document often contains a seriesof “coupons,” each of which is good for travel on a single flightsegment and information pertaining to how the travel was priced. Afterpurchase, a ticket document may have an entry in the airline'selectronic ticket database that contains a pointer to an active PNR inthe reservation database, via the PNR's record locator. Typically, a PNRcontains little or no information about the price of the travel or themethod of payment. Although a ticket document and a reservation areoften linked together, it is possible to have a reservation without aticket document. For example, the ticketing process that issues theticketing document can happen almost simultaneously with booking thereservation, or it may happen after a period of time (e.g., a week) haspassed. It is also possible to have a ticket without a reservation. Forexample, if a ticketed passenger decides not to travel on a ticket thathe has purchased, he will typically cancel the reservation but retainthe ticket.

Both the reservation and the ticket may have useful value. A ticketgenerally has direct, e.g., monetary value, since it may be convertedinto cash or exchanged for another ticket. A reservation's value howeveris less direct. A reservation's value is related to the inventory thatthe reservation controls, e.g., in a booking code that is no longeravailable. The airline industry typically operates in a manner thatcanceling inventory does not imply that the canceled inventory may bere-booked immediately or at all, either by the current holder or anothertraveler. A reservation may also have value purely by virtue of the timeit was produced, since many of the cheapest fares have requirements thatthe flights be reserved a certain period of time in advance ofdeparture.

Server

Referring to FIG. 2, the server 12 may be any type of computing deviceor multiple computing devices (e.g., a server farm). The server 12includes a processor 40 and memory 42 that executes software 44. Theserver also includes a historical database 20 that is stored in memory42. The software 44 includes the search engine 18, the refund/reissuelogic 19, and a Web server application 46 for enabling communicationwith the client 14 The Web server application 46 includes one or moreroutines used in implementing the TCP/IP protocol, which allows theclient computer 14 to communicate over the network 22. The server 12also includes an operating system software environment 48 that includes,but that is not necessarily limited to, an operating system 50, such asLinux. The refund/reissue logic 19 includes ticket reconstruction logic52, scheduler logic 54, reissue method logic 56, faring logic 58, andavailability logic 59.

Using the information associated with the original ticket supplied inthe query, the reconstruction logic 52 performs a historical pricingquery, or other similar processing, using the historical database 20 toreconstruct the pricing solution that was used to issue the originalticket.

The pricing solution, as reconstructed, includes fare rules associatedwith fares used in the original pricing solution. The fare rulesdetermine the conditions under which the fares were applied to theoriginal ticket and are used to determine whether those fare rules andfares can be used to provide a reissued ticket, and if so, under whatconditions. The scheduler logic 54 retrieves sets of flights thatsatisfy the request for new travel specified by the user's query. Theflights may be retrieved from the database 26 of published flights orfrom other sources. The reissue method logic 56 determines whether theflights returned by the scheduler process may also satisfy the farerules specified by the reconstructed pricing solutions. The availabilitylogic 59 analyzes the flights returned from the scheduler logic 54 todetermine whether there are seats available on the flights for thechosen fares (in the context of the existing reservation) and discardsthose combinations for which no seats are determined to be available.The faring logic 58 determines a set of valid fares, taxes, andsurcharges for the remaining flights, following industry standard rulesregarding currency conversions. In addition to pricing solutions forreissued tickets, the server 12 can be configured to produce othertravel-related information as a result of a user query. For example, theserver 12 can produce routes or airline suggestions, optimal traveltimes and suggestions for alternative requests.

Client

Referring to FIG. 3, a client computer 14 at which a user 16 enters aquery specifying a change to a purchased ticket and receives pricingsolutions for reissue tickets reflecting the change is shown. The queryfor a new trip includes information needed by the server 12 to determinea set of pricing solutions for reissuing or refunding an original ticketbased on the new travel information and the original ticket. This newtravel information typically requires at minimum, an origin anddestination for the new travel and at least a portion of the informationcontained in the original ticket, to permit the process to reconstructthe original ticket. In addition, the information could also includetimes, dates, and so forth.

In some examples, the client computer 14 may be any type of web-enabledapparatus or system including but are not limited to a desktop computer,a laptop computer, a mainframe computer, a cellular telephone, apersonal digital assistant (“PDA”), and a controller embedded in anotherwise non-computing device. The client computer 14 contains one ormore processor(s) 40 (referred to simply as “processor 40”) and memory42 for storing software 44. The processor 40 executes software 44, whichincludes a Web client application 47 and operating software 48. The Webclient application 47 includes one or more routines used in implementingthe TCP/IP protocol, which allows the client computer 14 to communicateover the network 22. The operating software 48 includes an operatingsystem 50, such as Windows XP®, and a web browser 52, such as InternetExplorer®. The web browser 52 enables the user 16 to interact with a webpage (i.e., an electronic document) that serves as an interface betweenthe user and the search engine 18. The web page provides the user 16with an interface to enter queries for ticket changes and displayspricing solutions returned by search engine 18 in response to the user'squeries. The web page may also provide the user 16 with tools forcustomizing the display of the returned results (e.g., sorting theresults, extracting results of interest, and eliminating results thatare not of interest).

Although loosely described as a client-server model the system 10 can beimplemented in other configurations/architectures.

Historical Database

Referring to FIG. 4A, the historical database 20 is a database ofhistorical information used with the refund/reissue logic 19 todecompose an original ticket into fares, fare rules and schedulinginformation that existed at the time that the ticket was issued. Thehistorical database 20 includes fares and fare change information 53 andfare rules and rule change information 56. The fares and fare changeinformation 53 includes an index 55 and a fare data file 54 that storesfare data provided by sources such as ATPCO and/or other sources.Similarly, the rules and rule changes information 56 includes an index58 and a rule data file 57 that stores rule data provided by ATPCO andother sources. Fare and rule data files 54 and 57 hold the fare and ruledata as records. The indexes 55 and 58 include keys that specify anairline, endpoint cities, or other travel parameters and file offsetspaired to the keys. A file offset points to records of the fare datafile 54 that correspond to the key paired with the file offset. A fileoffset corresponding to a group of records includes at least an addressin memory where group of records start, and the number of records in thegroup. The file offset may also include the starting memory addresses ofeach record in the group. In addition to storing fares and fare rulesdata, the historical database 20 stores ancillary data, such asroutings, fare construction tables, currency exchange rates, taxes,flights, and time zone variations. In some embodiments, the historicaldatabase 20 includes a third index for accessing the ancillary datae.g., routing, fare construction tables, currency exchange rates, taxes,flights, and time zone variations.

Fare records generally specify a fare for a given flight along with aneffective date (i.e., the date on which the fare is in effect). Farerecords may also specify changes or cancellations of a fare. When faredata changes, ATPCO sends either a fare record having a change tag thatindicates that a new effective date of a particular fare or a farerecord (referred to as a “cancel record”) that cancels the fare. Foreach fare record that is received from ATPCO (or from another source),the historical database 20 stores the fare record in the fare data file54 along with the date on which the fare record was transmitted. Ratherthan applying changes or canceling fares, as directed by ATPCO, thehistorical database 20 stores all of the received fare records andtransmission times as the fare records arrive at the historical database20.

At the time of query of the database 20 for historical records, a farerecord reconstruction process 60 retrieves relevant fare records thatexisted before and during the time the original ticket was issued andstores those retrieved fare records in a temporary database 59. Thehistorical database 20 merges the retrieved fare records stored in thetemporary database 59 to provide the fare record that was valid when theoriginal ticket was issued.

Rule records include an effective date on which a rule for a given fareis in effect. Rule records also include a discontinue date on which therule is no longer valid. The discontinue date of some rule records maynot be specified, indicating, in effect, that the rule record is validindefinitely. When rule data changes, ATPCO sends a cancel record tocancel a rule or an update record to change the rule. In someembodiments, ATPCO sends update records having the discontinue date setbefore the effective date (i.e., effective tomorrow, discontinuetomorrow). In other embodiments, when ATPCO sends a change, they send anew rule record with an effective date that is the same as thetransmission date. When the historical database 20 receives a new rulerecord, a rule record reconstruction process 74 changes the discontinuedate on the previous record to the day before the effective date of thenew record. For each rule record that is received from ATPCO or fromanother source, the historical database 20 stores the rule record in therule data file 57 along with the date on which the rule record wastransmitted.

At the time of query, the database 20 retrieves the rule records thatexisted during the time the original ticket was issued. The historicaldatabase 20 restores the rule record to its original form so that itappears the way it had looked when the original ticket was issued. Forexample, if the rule record had an indefinite discontinue date at thetime the original ticket was issued, the historical database 20 restoresthe discontinue date of the rule record to be infinity, even though itmay have a finite discontinue date specified at the time of query.

Referring now to FIG. 4B, a fare record reconstruction process 60receives a query (61) for historical records and determines an index(63) and retrieves relevant fare records that existed before and duringthe time the original ticket was issued. The historical database 20searches through the records and determines (65) if the ticket wasissued before the transmission date of the record and if so removes (69)the record from consideration. The fare record reconstruction processmerges (71) the remaining retrieved fare records stored in the temporarydatabase 59 to provide (73) a candidate fare record that was valid whenthe original ticket was issued. In some embodiments, the merging process71 includes merging held inventory with live inventory.

Referring now to FIG. 4C, a rule record reconstruction process 74receives (75 a) a query for historical records and determines (75 b) anindex and retrieves relevant fare records that existed before and duringthe time the original ticket was issued. The historical database 20searches through the records and determines (76) if the ticket wasissued before the transmission date of the record and if so removes (77)the record from consideration. The rule record reconstruction process 74restores (78) rule record to its original form to provide (79) acandidate rule record that was valid when the original ticket wasissued. Unlike conventional schemes that store snapshots of fares andfare rules at different times in history, the historical database 20stores a record of changes to the fares and fare rules that are used toreconstruct fares and fare rules on the fly at the time of query ratherthan at the time the fare and rule records are received.

Some data sources provide data to the historical database 20 that doesnot include explicit update or cancel records for canceling or changingprevious data records. To handle data received from these types ofsources, the historical database 20 or server 12 includes a program thatlooks at changes and computes incremental changes between records andstores these incremental changes. The program looks for any index thatchanged at all, determines the changes that were made, and stores thechanges as additional records. For example, the program may insert acancel record between two records where one would ordinarily be.

Under some frequently occurring circumstances, the exact time and dateof ticket issuance and/or pricing is not known. To deal with suchcircumstances, the above algorithm is modified to take a time rangeinstead of a single point in time. The result of the fare and ruleretrieval processes are then sets of records, each labeled with abeginning and ending timestamp identifying the time period during whichthe record was valid.

Typically, tickets are only valid for one year from commencement oftravel (which itself may be up to a year from the date of purchase) andthis places a limit on how much historical data that needs to bemaintained in the historical database 20. Even seemingly staticdatabases, such as databases of city and airport codes, need to havehistorical versions to deal with the small number of changes that occurto them over the course of a year. Data is stored in the historicaldatabase 20 for a limited period of time (e.g., 25 months), after whichit is purged to make room for new data.

To improve speed of data retrieval, the historical database 20 isimplemented as a memory mapped file system that can be directly accessedfrom memory 42 by the processor 40. Although the historical database 20could also be implemented as a relational database, in someimplementations a memory mapped implementation is preferred. In someembodiments, the historical database 20 includes two separate indexes tothe same fare and rule data: a first index referencing only to currentdata and a second index referencing both current and historical data.Having two such indexes can be used to speed up access to current data.The historical database 20 may also store information in a data file asthe information arrives from ATPCO or other data sources and use theinformation to reconstruct the original ticket at the time of query.

Server Process

Referring now to FIG. 5, refund/reissue logic 19 for providing newpricing solutions to satisfy changes to a purchased ticket is shown. Therefund/reissue logic 19 is preferably executed on the server computer12, but could be executed on the client computer 14. The refund/reissuelogic 19 receives (62) a query from the user 16. The query includesinformation needed by the server 12 to determine a set of pricingsolutions for issuing a new ticket that satisfies the requested newtravel requirements using some value associated with an original, issuedticket. This information typically requires at minimum, an origin anddestination for the new travel and at least a portion of the informationcontained in the original ticket and/or PNR. The query may specify otherinformation related to the original ticket, for example, flight segmentsthat have already been flown, information about taxes paid, etc.

The refund/reissue logic 19 reconstructs (64) the ticket based on thereceived query in reconstruction logic 52 (FIG. 2). The reconstructionlogic 52 queries (not shown) the historical database 20 usinginformation associated with the original ticket supplied in the query.The historical database 20 returns one or more possible sets of faresand rules, referred to as “candidate fares and rules,” whose associatedrecords contain information that matches the information associated withthe original ticket. The reconstruction logic 52 may narrow down thereturned pricing solutions by evaluating the rules associated with thefares in the context of the original ticket. The result is a set of“candidate reconstructed tickets.”

The refund/reissue logic 19 determines (66) possible itineraries, thatis, sequences of flight segments, between the origin and destination foreach portion of a new trip, which can satisfy the new travelrequirements specified in the query. The scheduling uses the schedulerlogic 54 (FIG. 2) in combination with the search engine 18 (FIG. 2) toproduce a large number of such itineraries. Examples of schedulersystems to provide itineraries to the scheduler logic 54 that may beused include the scheduling component of the QPX search engine, or alsoequivalently other products such as OAG Flight Desk (Official AirlinesGuide, a division of Reed Travel Group) or schedule components ofcomputer reservation systems (CRS's) such as Sabre®, Apollo®, Amadeus®and WorldSpan®. In some embodiments, the scheduler logic 54 isconfigured to obtain the largest number of possible itineraries. Theavailability logic 59 (FIG. 2) analyzes the pricing solutions returnedfrom the scheduler logic 54 to determine (67) whether there are seatsavailable on flights of the itineraries. The availability determination(67) eliminates those itineraries for which there are no seatsavailable. The candidate solutions determined (64) using thereconstruction logic 52 and the itineraries for replacement ticketsreturned from the availability logic 59 are fed to the reissue methodlogic 56.

The reissue method logic 56 (FIG. 2) determines (68) for each candidatereconstructed ticket which, if any, valid reissue methods may be used torefund or exchange it with one or more of the proposed replacementitineraries returned from the scheduler logic 54. A reissue methodspecifies a type of change that may be made to a ticket and theconditions under which the change is made. Reissue methods may alsoinclude canceling and refunding at least a portion of an originalticket. For example, a reissue method for canceling a ticket andreceiving a full refund may require the ticket holder to cancel theticket at least two weeks before the scheduled departure. The reissuemethod logic 56 may eliminate candidate reconstructed tickets for whichno reissue methods exist and reissue methods that are not applicable toany combination of candidate reconstructed tickets and replacementitineraries. After evaluating reissue methods in the context of thecandidate reconstructed tickets and the replacement itineraries, thereissue method logic 48 returns the reissue methods that allow one ormore of the candidate reconstructed tickets to be replaced by one ormore of the proposed itineraries.

The reissue method logic 56 provides reissue methods and sets ofcandidate reconstructed tickets and reissue itineraries that areapplicable to each of the reissue methods to the faring logic 58. Thefaring logic 58 determines (70) valid fares corresponding to thereplacement itineraries produced by the itinerary determination process66 (also referred to as scheduler process 66) according to the reissuemethods that are valid for the replacement itineraries. In determining(70) valid fares, the faring logic 58 calculates the final prices of thereissue solutions that may include taking deductions based on theexisting ticket (fare or tax amounts paid) and adding penalty amountsspecified by the reissue methods. The refund/reissue logic 19 on theserver 12 sends the reissue pricing solutions to the client 14. Afterreceiving a user's selection of one of the pricing solutions from theclient 14, the server 12 initiates (72) a booking process to provide abooking and reservation for the user 16 based on the selected pricingsolution. The booking process (72) is optional and may be performed byan external booking system.

Ticket Reconstruction Process

Referring to FIG. 6, the ticket reconstruction process 64 (FIG. 5)performed by the ticket reconstruction logic 52 is shown in furtherdetail. The information that can be supplied about a ticket andreservation (such as what is written on the paper version of a ticket,what is contained in the airline ticketing database, or what iscontained in the PNR) is not necessarily sufficient to unambiguouslydetermine how the ticket was originally priced. Furthermore, even if thefares themselves are determined unambiguously, the rules for reissue andexchange of tickets may require information that is not contained on theticket, such as the structure of the “priceable units” contained on theticket. The ticket reconstruction logic 52 queries (82) the historicaldatabase 20 using information pertaining to the original ticket,including information on the ticket and from a PNR, provided in theuser's query.

The historical database 20 returns the fare records having informationthat matches the information supplied in the query. In some embodiments,the fare records in the historical 20 database contain informationfields including: a carrier, a city pair, a fare basis code (analphanumeric identifier), a tariff number, a rule number, a fare tag(one-way, round-trip, or one-way-only), the price for the particularfare record, and dates, such as the transmission date of the record andvalidity date or dates of the record. Typically, the user's ticketincludes only a subset of the fields for each of the fares that itcovers. For example, the fare information contained on the ticket may belimited to the following fields: the carrier, cities, fare basis code,price, and issue date. Because fare records may differ by any of thedatabase information fields, there may be multiple entries in thedatabase that match fields listed on the ticket; each is a potentialmatch for the fare listed on the ticket.

In some instances, the data in the fields listed on the ticket may beincorrect or unreliable. Examples of such instances include thefollowing: the fare rules may specify modifications to how the farebasis code is printed on the ticket; the price listed on the ticket isnot the price in the fare record, but rather it is the sum of the farerecord price with some applicable surcharges for the fare; the issuedate of the ticket may not be the date when the ticket was priced; andthe fares used on the ticket may originate from an unknown date if theticket has been reissued previously.

The historical database 20 also includes fares that are constructedthrough various processes, including: processes that produce constructedfares (e.g., international fares which are pieced together from a“published base fare” and one or two “arbitraries or add-ons”), andprocesses that produce a “fare by rule fares” (e.g., fares that areproduced from other fares or for all markets in a geographic area).Thus, it is important that the correct fare records are retrieved fromthe historical database 20, since the methods available for changing aticket depend on the rules attached to the fares on the ticket.

After a set of candidate fare records are returned by the historicaldatabase 20 in response to querying the historical database (82), thereconstruction logic 52 optionally evaluates (84) the rules of thecandidate fare records in the context of information in the originalticket. In one implementation of the reconstruction logic 52, it isassumed that the system that priced the original ticket evaluated farerules associated with the fare used to price the original ticket. Thereconstruction logic 52 can dismiss, as candidate matches, any farewhose rules “FAIL” when the rules are applied to the flights of theoriginal ticket, because the original pricing system would not have usedthose fares whose rules had failed. For example, the reconstructionlogic 52 checks whether any special conditions specified in thecandidate fare records such as day of week, seasonality, Saturday nightstay, advance purchase, etc. are satisfied by the original ticket. Upondetermining that one or more rules of a candidate fare record areviolated, the reconstruction logic 52 eliminates the candidate farerecord from consideration. In addition to rules which apply to theflights on the tickets, fares may also fail combinability constraintswith each other.

The ticket reconstruction process 64 (FIG. 6) determines (86) if atleast one candidate solution has been returned by the rule evaluatingprocess 64. If no solutions are found, the ticket reconstruction process64 progressively relaxes (88) or waives certain rules and re-evaluates(84) the candidate solutions until at least one candidate solutionpasses the evaluation. For example, it is possible that thereconstruction process 64 will fail to produce any valid ticketscomposed of the candidate fare records. This can happen for a variety ofreasons, including: (1) data in one or more fields listed on the ticketbeing incorrect or unreliable, (2) the ticket was issued by an authoritythat had access to fares that are not stored in the historical database20, (3) one or more fare rules were overridden to produce the originalticket, and (4) ancillary data used by the pricing system that issuedthe original ticket (e.g. exchange rates, international taxes, etc.)does not match the ancillary data of fare records stored in thehistorical database 20. In some embodiments, the reconstruction logicassigns a penalty value for each violated rule, and for each fare recordthat violates a rule, the reconstruction logic 52 sums the penaltyvalues associated with rules violated by the fare record. Thereconstruction logic 52 can then determine which of the fare recordsviolated the least number of rules or pose the least serious kinds ofviolations by determining those fare records having the lowest sum ofpenalty values.

Alternatively, all combinations of fares and flights can besimultaneously considered, and a configurable penalty assessed for eachrule violation; the pricing solution with the lowest penalty can then bechosen.

In some embodiments, the reconstruction logic 52 (FIG. 2) collectsinformation used to eliminate the candidate solutions, including rulesthemselves that were violated, and returns the collected information tothe user 16 or to an administrator in a report. The user oradministrator may analyze the report to make an informed decision aboutthe correct course of action regarding the violated rules. For example,the user 16 or the administrator might instruct the ticketreconstruction logic 52 (FIG. 2) to waive certain conditions or force amanual pricing of one or more candidate solutions that had beeneliminated.

If at least one candidate solution exists, the process (64 of FIG. 6)determines (90), if multiple candidate solutions exist. This may occurif insufficient information has been provided (for instance, theidentification of the agency that issued the original ticket, or theexact time that the previous price was computed may be unknown), or itmay occur if there were actually multiple valid candidate solutionscorresponding to the original ticket. A source of ambiguity that maylead to multiple valid candidate solutions is the “priceable unit”structure of the final answer. The airline industry enforces certainconstraints on a ticket pricing structure by grouping fares on a ticketinto “priceable units” and enforces rules within the context of thesepriceable units. It is common for multiple different priceable-unitstructures to result in tickets that are otherwise identical, includingfinal price. If the priceable unit information is not supplied in thequery, the process 64 of reconstructing the ticket may result in anun-resolvable ambiguity of seemingly valid multiple candidate solutions.The presence of multiple candidate solutions matter to the extent thatthe multiple candidate solutions influence options available forchanging the ticket.

If only one candidate solution exists, the reconstruction logic 52returns (94) that solution to the scheduler process 66 (FIG. 4). If,however, multiple candidate solutions exist, the reconstruction logic 52sends (92) a request to the user 16 or possibly to an administrator todisambiguate the results. After the results are disambiguated, theprocess returns (94) one or more candidate solutions selected by theuser 16. In some embodiments, the reconstruction logic 52 may attempt todisambiguate multiple results by determining if there is only onecandidate solution whose total price of the results that matches thetotal price of the existing ticket, and selecting that candidatesolution. In other embodiments, the process 60 simply returns (94) allof the candidate solutions remaining after the rules evaluationprocedure (84) without sending a request to the user 16 to disambiguatethe results (92). All of these candidate solutions would then be carriedforward into the reissue process equally, and the most advantageouscandidate chosen for each possible reissue pricing solution.

Scheduler Process

Referring to FIG. 7, the scheduling process 66 (FIG. 5) (also referredto as itinerary determining process 66) by which the scheduler logic 54identifies possible flight schedules that satisfy the new travel requestis described in further detail. In a situation where new tickets wouldotherwise be very expensive, it may be very advantageous to make use ofas much of the existing ticket as possible. Thus, when producing a listof possible replacement itineraries, the scheduler logic 54 receives(81) from the search engine 18 sets of flights that satisfy the requestfor new travel specified by the user's query, examines (83) the flightson the original ticket and returns (85) the itineraries for areplacement ticket that include one or more of the original flights,even if the flights might not normally be considered by a regular travelplanning system (e.g., because the flights are deemed too circuitous).For example, if the passenger is holding tickets for a round-trip, e.g.,from Boston to Miami via Atlanta, but now wishes to make a last minutechange to go to, e.g., Seattle instead of Atlanta, there may be greatvalue (in terms of lower cost or even priority in securing seats) inconsidering trips that go through Atlanta (or even Miami) to get toSeattle, though such itineraries may be less time efficient.

Availability Process

Referring to FIG. 8, the availability determination process 67 (FIG. 5)by which the availability logic 59 determines whether the replacementitineraries returned by the scheduler logic 66 are available isdescribed in further detail. The availability logic 59 interrogates (87)the inventory database 26 to determine (89) whether there are seats andfares available on particular flights for the replacement tickets andremoves (91) from the set of replacement itineraries those itinerariesfor which there are no seats or fares available. While therefund/reissue logic uses the information contained on the ticket, evenif no seats or fares are currently available in the inventory categoryheld by the user 16, the availability logic 59 allows the user 16 toretain those seats and fares, subject to airline rules.

Contained within some PNRs are a set of “married segment indicators.”Married segment indicators used by the airline industry are integersassociated with flight segments that indicate which flight segments ofthe inventory held in the PNR are to be considered together as distinctunits. If one segment with a particular married segment indicator iscanceled, then all segments with that indicator must be canceled. Thisprevents changes to the PNR that allow the passenger to retain some ofthe married segments while canceling others. Generally, segments aremarried within a PNR to indicate that the inventory was granted to apassenger on the assumption that they would travel on (and pay for) allof the segments. For example, a passenger may have bought a ticket fromBoston to LA connecting in Dallas. If the two segments are married, thepassenger cannot keep the Boston to Dallas segment and cancel the Dallasto LA segment.

In determining availability of flights on the replacement ticketsreturned from the scheduler logic 54, the availability logic 59 marks(93) the replacement itineraries with potential marriage indicators(discussed below). For sequences of flights that overlap partially withthe inventory currently held in a PNR, the availability logic 59 merges(95) availability counts from these sequences of flights with theinventory from the PNR, in accordance with the marriage indicators. Foreach response to an availability query for an overlapping sequence offlights, if the response contains a marriage indicator for the samesubsequence as a married subsequence currently held in the PNR, theavailability logic 59 produces (97) a record associated with theresponse that includes the counts for the subsequence of flightsreplaced with a placeholder record representing that married sequencefrom the PNR, with only currently held inventory available. The countsused in these placeholder records are given by the number of passengersin the existing PNR. The PNR holds inventory for the passenger; thereissue is accomplished by editing the PNR. The passenger is allowed tokeep inventory they have from the original booking, or use new inventoryavailable now. Pseudo code for the availability determination process 67is:

Save away the currently held inventory.  Perform a live availabilityquery for current availability  for each itinerary   letP[length[itinerary]] = { { } }   for f from length[query]−1 downto 0   IF (flight in itin at f matches a flight on the ticket)     AND(flight on ticket is the start of a married group)    THEN     letticket-av = list of booking-codes used on this          married group onthe ticket     let l = length of married group     for each R in P[f +l]     P[f] = P[f] union (ticket-av + R)    ENDIF    for eachavailability answer for itinerary     IF (flight in itin at f is startof a married group in      answer)     THEN     let answer-av = list offlight availabilities for          this married group     let l = lengthof married group     for each R in P[f + l]       P[f] = P[f] union(answer-av + R)     ENDIF   add the new answers in P[0] to the set ofanswers for this    itin

Although the availability determination process 67 is shown after thescheduling process 66 in FIG. 5, the availability determination process67 could be included as part of the faring process 70 (or at otherpoints in the processing) to eliminate pricing solutions for which noseats are available for one or more flights.

Reissue Method Process

Referring to FIGS. 9A-9B the reissue method determination process 68(FIG. 5) performed by the reissue method logic 56 is shown in furtherdetail. Given a reconstructed ticket, the reissue method logic 56determines what options are available for refunding and/or exchangingthe ticket. For a given ticket, one or more different types of changemechanisms, referred to as “reissue methods”, may be allowed. Somereissue methods issue a new ticket to replace an existing ticket whileother reissue methods involve canceling the ticket and providing theholder a refund, and then buying a new ticket (not technically a ticketreissue). A reissue method specifies a type of change to an issuedticket and conditions under which that change may be made.

A reissue method includes one or more of the following components:

(1) conditions on the original ticket (e.g., partially flown vs.completely unflown, ticket still valid for travel or not, exchangebefore or after departure, current time within the original “ticketingtime limit”, passenger type at time of original ticket purchase, whetherthe ticket has previously been reissued or not, etc.);

(2) a source for fares used for re-pricing (e.g., keep all fares onoriginal ticket, keep fares for unchanged flights, current fares forchanged flights, historical fares from the time of ticket issue for allflights, and many other combinations);

(3) rule waivers for re-application of ticketed fares to new flights;

(4) mechanisms for validating advance purchase restrictions;

(5) conditions on the new ticket (e.g., must not change the first farecomponent, must not change fare breakpoints, specific restrictions onwhat fares may be used, the ticket must cost more than the previousticket);

(6) change penalty amounts;

(7) changes in a form of payment or refund to be applied to the reissuedticket (e.g., cash refund, a refund in the form of credits that can beapplied toward the purchase of a future ticket).

Given a reconstructed ticket, the reissue method logic 56 determines(100 of FIG. 9A) whether changes can be made to the reconstructedticket. To accomplish this determination, in some embodiments, thereissue method logic 56 examines the validating (ticketing) carrier ofthe reconstructed ticket, the carrier or agency performing the newtransaction, the proposed new validating carrier, and the group ofcarriers whose fares and flights appear on the ticket. Based on thisinformation, the reissue method logic 56 determines whether changes tothe ticket can be processed, and if so, which reissue methods areapplicable to processing the ticket. If the reconstructed ticket doesnot permit any changes to be made, the reissue method logic 56 prices(101) an entirely new ticket satisfying the new desired travel, andoptionally computes any residual value that the ticket may have, whichmay be zero.

Since the number of reissue methods may be large (e.g., for ATPCOcategory 31 (voluntary changes) and ATPCO category 33 (voluntaryrefunds) processing, the number of possible combinations can beexponential in the number of fares on the original ticket), it isdesirable to eliminate non-applicable reissue methods as early aspossible to avoid unnecessary computation. Reissue methods are oftengeneralized such that they apply to large sets of possible tickets. Atan early stage of the reissue method determination process 68, thereissue method logic 56 filters (102) the reissue methods down to onlythe set of reissue methods that applies to the actual reconstructedticket or tickets being considered. The properties of a reconstructedticket, such as whether it has been partially flown and whether the newtransaction is within the “ticketing time limit” of the original ticket,and information present on the ticket are compared to the each of thereissue methods. The reissue method logic 56 eliminates any reissuemethods whose requirements are violated by all of the candidatereconstructed tickets.

By filtering (104) the remaining reissue methods with respect to theconstraints of the query for new travel, the reissue method logic 56attempts to eliminate more of the reissue methods from consideration.For example, if the new travel specified in the query does not includeany travel on the outbound travel date of the original ticket, anyreissue method that requires keeping the flights of the first farecomponent can be discarded. In some embodiments, the reissue methodlogic 56 performs more aggressive filtering including pre-evaluatingadvance purchase restrictions using the advance purchase processingmechanism from the reissue method based on the query-specified desireddeparture time range. Performing more aggressive filtering may alsoinclude determining whether a reissue method enables the farebreakpoints of the original trip to remain unchanged given the requestednew trip.

The reissue method logic 56 considers reissue methods for possiblepricings of possible replacement itineraries by maintaining a statusvector over the possible reissue methods in data structures representingpartial pricing solutions of the replacement itineraries. A partialpricing solution includes a fare and itinerary that partially satisfythe new travel request. For example, a replacement ticket may becomposed of multiple partial solutions each including a flight segmentof the replacement itinerary and a fare associated with the flightsegment. One technique to track applicable reissue methods is to use astatus vector. A status vector of a partial pricing solution indicatesthe types of reissue methods that apply to the partial solution. In someembodiments, the position of a bit represents a reissue method and a “1”in the status vector at the position represents that at a particularstage of processing, the corresponding reissue method might still bepossible for this partial pricing solution (in other words, the reissuemethod is not known to be inapplicable on all possible reissue pricingsolutions which can be built from this partial pricing solution). Otherapproaches could be used.

In some embodiments, two “special” reissue methods are allocated andassigned to the first two bits in a status vector. These bits representtwo possibilities. The first bit represents a reissue method thatinvolves pricing a completely new ticket. Partial pricing solutions forflights in the future, using fares that are currently available, andwhich do not require waiving any fare rules may qualify for this specialmethod. The second bit represents a reissue method that enables totalreuse of the original ticket. This type of reissue method applies to theticketed flights using the ticketed fares, regardless of whether rulesfail or not. Under this reissue method, the passenger should be able tokeep their ticket and inventory without change penalty regardless of anyother constraints.

The reissue method logic 56 determines (106 of FIG. 9A) valid reissuemethods for each of the partial pricing solutions and updates thecorresponding status vectors of the partial pricing solutions. A statusvector of a particular partial solution having all zero bits indicatesthat no reissue method, including a whole new ticket, would allow thepartial solution to occur as part of a replacement ticket. The reissuemethod logic 56 filters (108) the partial solutions having zero statusvectors from the partial solutions having non-zero status vectors andeliminates the zero partial solutions from consideration.

The fare rules associated with the partial solutions determine thepricing of a replacement ticket composed of the partial solutions. Whenapplying fare rules in a fare-component context (i.e., when the flightsto paid for by the fare have been chosen, but the other flights in thenew trip are not yet known), the system evaluates whether the flightsbeing considered are all present, in sequence, and on the originalticket. If the flights being considered are all present in sequence onthe original ticket and booked in the same inventory, the flights areconsidered unchanged flights; otherwise the flights are changed flights.Similarly, the fare itself can be checked to see if the fare occurs onthe ticket, and whether it is a historical fare or a current fare.

The reissue method logic 56 evaluates (110 of FIG. 9B) the rules of thepartial pricing solutions to determine the requirements they place onwhich type of fare is used on which type of flight sequence. In somecases, based on the evaluation, the reissue method logic 56 eliminatesreissue methods associated with the partial pricing solutions based onthe requirements the eliminated reissue methods would place on the typeof fare used on and the type of flight sequence. However, the reissuemethod logic 56 may not be capable of completely evaluating some of therules governing the combination of fares and flights at this time. Oneexample is the requirement that ticketed fares be used up until thefirst change, and current fares used thereafter. The reissue methodlogic 56 may evaluate governing the combination of fares at multipletimes throughout the reissue method determination process 68. Forexample, some combinations of fares may “FAIL” immediately (e.g. aticketed fare on a changed flight); some combinations of fares may“FAIL” when combined into priceable units (e.g. the combination into apriceable unit of a changed flight with a ticketed fare on a laterunchanged flight); and combinations of fares may “FAIL” at the finalstage when priceable units are combined into new trips (e.g. twopriceable units that each obeys the restriction independently, but wherethe combination of a particular fare and flight puts a ticketed fare ona ticketed flight after the first change). The result of the ruleevaluation (110) is either a PASS, FAIL, or DEFER.

A determination is made (112) as to whether the rule check of step 110returns a FAIL at each level of processing, as larger partial solutionsare built up from smaller pieces. If a FAIL result is not returned, thepartial solutions are passed through to the next higher level. At thehighest level, if the rule still does not fail, the result is passed onto the next stage of processing.

When a normal rule check would return FAIL, the reissue method logic 56determines (114) if any reissue method would allow the rule to beevaluated differently, and if so, what the result would be under theless restrictive evaluation. Some reissue methods allow the waiving ofcertain fare rules or modify the behavior of the rule evaluation process110. For example, one or more reissue methods may enable rules thatimpose advance purchase requirements to be modified to allow partiallyflown trips to be re-priced. As long as the reissue methods change therule evaluation behavior such that the new behavior is less restrictivethan the normal behavior, a simple modification to the rule evaluationprocess is sufficient. Because rule applications only become lessrestrictive under the reissue methods, a PASS or DEFER result would alsoapply under the less restrictive rule as directed by the reissue method.This mechanism can be modified to handle the case where the ruleevaluation becomes more restrictive under a particular reissue method,or where there are multiple levels of progressively loosenedrestrictions. All that is required is that the application of the ruleevaluation proceeds from most restrictive to least restrictive.

If the reissue method logic 56 determines, for a given partial solution,that there are no re-issue methods that could modify the violated ruleso that it does not still fail, the reissue method logic 56 eliminates(116) the partial solution from consideration. If however a reissuemethod that enables modification of a violated rule is determined (114),the status vector of the partial solution is updated (118) to includethe reissue methods that would allow the modified rule check. Thisupdated status vector is combined with the existing status vector of thepartial solution (e.g., using a logical AND operation) to produce afinal status vector indicative of all reissue methods that are valid forthe partial solution. The process 68 checks (120) whether an entireticket has been constructed and keeps looping over larger and largerpartial solutions until the entire ticket is constructed. Once theentire ticket is constructed, the process 68 outputs (122) theconstructed ticket to a subsequent process (e.g., faring process 70).

Faring Process

Referring to FIGS. 10A-10B, the faring process 70 (FIG. 5) by which thefaring logic 58 determines pricing solutions for the replacementitineraries is shown. As described above, there are a number ofconditions that reissue methods may apply to the new ticket. Examplesare that the flights of the first fare component of the old ticketappear on the new ticket or that none of the fare breakpoints of the oldticket may be changed.

The faring logic 58 examines (132 in FIG. 10A) the sequences of flightsthat are to be considered for the new travel request query. For eachitinerary combination that covers the entire new trip, the faring logic58 determines (134) division methods for dividing the flights into farecomponents. For each of these division methods (potential farecomponents), the faring process 70 enumerates (136) fares applicable tothe flights. Fares that are found by the rule evaluation process(including reissue method evaluation) to be possibly valid for theflights are carried forward to the priceable unit construction process.At the priceable-unit level, the faring logic 58 has access to both theexact flights and the fare breakpoints that will be used to construct acomplete priceable unit. Priceable units that pass rule evaluation(including reissue method evaluation) at this level go forward to thelinking process. During linking, the faring logic 58 performs a finalevaluation (138) of the reissue methods with respect to the ticketconditions, and disqualifies the methods that do not satisfy theirconditions. The faring logic 58 analyzes (140) the status vectors ofeach priceable units and groups (142) together the priceable units thathave some valid reissue methods in common. Reissue methods typicallyremain for each group of priceable units, since the reissue methods tendto be disjoint in the types of changes that they allow. However, it isstill possible that many groups of priceable units will satisfy morethan one method. For priceable units that contain only current faresused on flights in the future, the all-new-ticket method will typicallyapply in addition to any carrier-specified methods that may beavailable.

For each group of pricing solutions, the faring logic 58 determines(144) if the corresponding reissue methods allow the price of theprevious ticket (i.e. previously paid fare or tax amounts) to be appliedtoward the value of the new ticket. Reissue methods that specify an“all-new-ticket” method will generally prohibit such discounts. Thefaring logic 58 also computes (146) any change penalty amount for eachreissue method. The sum of the original ticket discount and the changepenalty is referred to as the “total adjustment amount.”

The faring logic 58 produces complete pricing solutions from priceableunits through a process 148 called “linking.” During the linking process148, the faring logic 58 combines the priceable units within each groupto form a set of pricing solutions for replacement tickets that satisfythe user's query. To account (150) for any adjustment amounts, thefaring logic 58 subtracts out the value, if any, of the original ticket(fare or tax amounts) from the price of the replacement ticket and addsto the price of the replacement ticket any penalty amounts that havebeen calculated.

In some embodiments, such as when using the refund/reissue logic 19 inconjunction with a travel planning system, as described in U.S. Pat. No.6,275,808, the pricing solutions are represented using a compactstructure called a “pricing graph.” The pricing graph is divided intogroups of pricing solutions based on the sets of reissue methods thatare valid for generating the groups of pricing solutions. The faringlogic 58 loops over all possible reissue methods for each group ofcomplete pricing solutions (represented by the reissue-method statusvector on the link-fringe) and tags the group of complete pricingsolutions corresponding to a reissue method with the resultingadjustments so that the groups of solutions as represented in the graphhave the correct total cost.

The pricing solutions are presented (152) to the user 16 at the client14. In some embodiments, only the group of complete pricing solutionscorresponding to the reissue method which results in the lowest totaladjustment amount is presented to the user 16. After the server 12receives a ticket selection from the user 16, the booking process 72(FIG. 5) provides the user 16 a booking and reservation for the ticketselection.

User Interface

Referring to FIGS. 11A-11E, different user interfaces may be used topresent replacement ticket options to the user 16 and to highlight thedifferences between the existing purchased ticket and the replacementticket options returned by the search engine 18.

FIG. 11A shows a user interface 160 that displays a summary ofreplacement ticket options returned by the search engine 18.

FIG. 11B shows a user interface 162 that displays the itinerary of theexisting ticket above possible replacement options to enable the user 16to more easily compare and contrast the existing ticket and thereplacement options. One disadvantage of this model is that the user mayneed to look back and forth between the existing ticket and thereplacement options, comparing characteristic for characteristic, todetermine the differences between the replacement option itineraries andthe original ticket itinerary.

FIG. 11C shows a user interface 164 that attempts to solve this problemby highlighting the differences between each replacement itinerary andthe original ticket itinerary. The highlighting in this instance is donein a different shade of color on a multi-colored display. See trips 1and 3 under the Date, Flight times and Duration headings.

FIG. 11D shows a user interface 166 that displays the differencesbetween the existing ticket and a replacement option inline with eachreplacement itinerary. Although the user interface 166 uses more spacethan the user interface 164 of FIG. 11C, it reduces the difficulty anddistance the users' eyes must travel back-and-forth between original andreplacement itineraries. Again, different shading (of gray or color) isused to highlight the differences.

FIG. 11E shows a user interface 168 that replaces the differencesdisplayed as highlighted text in the user interface 166 of FIG. 11D withstrikethrough text. In some embodiments, one or more of the userinterfaces 164, 166, and 168 include a set of buttons that controlswhether or not to display differences between the original ticket andthe candidate replacement itineraries. For example, if the user 16 doesnot want to see the differences shown in one or more possiblereplacement itineraries, the user 16 can select a button or multiplebuttons that causes the differences to disappear.

The user interfaces 164, 166, and 168 may also include controls thatenable the user 16 sort the possible replacement ticket optionsdisplayed. In addition to enabling the user 16 to sort replacementticket options by price, departure time, carrier, duration, class ofservice, warnings, and other standard travel parameters, the controlsalso enable the user 16 to sort replacement ticket options according tothe number of differences between the replacement itineraries and theitinerary of the existing ticket. For example, the user 16 may preferthose replacement options for which the number of differences is thesmallest.

The user interfaces 160, 162, 164, 166, and 168 may include controlsthat enable the user 16 to select and highlight various types ofdifferences between the existing ticket and the replacement ticketoptions. For example, if the user 16 decides to take an earlier flight,the user 16 may want to highlight only those differences that correspondto originating flights. Similarly, the user 16 may want to un-highlightdifferences that are of no interest.

When specifying a search for options to replace an existing ticket, auser may specify their search differently from the initial search theyperformed when they bought their existing ticket. Depending on whatinformation is stored and captured about the user's intent (i.e., thecharacteristic(s) of the existing ticket that the user 16 is explicitlyattempting to change), the user interfaces 160, 162, 164, 166, and 168can discriminate between explicitly requested differences between theexisting ticket and candidate replacement options and consequentialdifferences that were not explicitly requested.

For example, when highlighting differences between the original ticketand the possible replacement options, the user interfaces 160, 162, 164,166, and 168 may highlight explicit differences and consequentialdifference in different colors or formats. In some embodiments, the userinterfaces 160, 162, 164, 166, and 168 highlight differences between thetravel options that were available when the search for the originalticket was performed and the travel options that are available at thetime of the user's query for replacement ticket options. In someembodiments, the user interfaces 160, 162, 164, 166, and 168 include aseparate “details page” for displaying the differences between theoriginal ticket and a possible replacement options in an inlinearrangement.

QPX Implementation

The travel planning system 10 and its operations may be implementedusing the QPX travel planning system, as described in U.S. Pat. No.6,275,808 and briefly discussed above. One technique to use therefund/reissue logic 19 with the travel planning system, as described inU.S. Pat. No. 6,275,808 involves certain modifications to the low faresearch (LFS) algorithm described in that patent.

As described above, the reissue method can use a status vector to trackapplicable reissue methods. To adopt the LFS technique for use with therefund/reissue logic 19, the LFS technique is modified to trackpotential reissue methods using the status vector.

Thus, when a fare is first considered at the faring-market level ruleevaluation, the reissue-method status vector is initialized, e.g., toall ones because the reissue methods are initially assumed to pass untilthey fail. The rule checkers (used at all levels of rule checks) aremodified to relax rules, and when the rule checks relax the rules therule checks return a marker status vector indicating the subset ofreissue methods which allow the particular relaxation that wasperformed. For fare-components, priceable unit-labels, link-label-sets,and link-fringes, each data structure is provided with an additionalfield, “REISSUE-STATUS,” which is a status vector over the reissuemethods, indicating the state (e.g. known to fail, unsatisfiedconstraint, etc.) for the set of partial pricing solutions, at thatparticular solution stage, which the fare-component, priceableunit-label, link-label-set, and link-fringe data structures represent.

When considering fares after the faring-market level rule checks, logicis added to evaluate each reissue method along with the set of markerstatus vectors returned by the rule checker to produce a reissue statusvector. The resulting reissue status vector is passed directly along tothe fare-component level rule check. When considering combinations offares with flights, after the fare-component level rule checks, logic isadded to evaluate each reissue method in the context of the farecomponent, in addition to the set of markers returned by the rulechecker. The resulting reissue status vector is stored on thefare-component. When considering flights in the context of apriceable-unit, after priceable-unit level rule checks, logic is addedto evaluate each reissue method in the context of the full set offlights of the priceable unit in addition to the set of markers returnedby the faring market set level and priceable-unit level rule checkers.

The priceable unit level rule checker logic considers each reissuemethod that is listed as a possibility in all fare-components of thepotential new priceable-unit, as well as being a possibility in anymarkers returned by rule checks. The resulting reissue status vector isstored on the priceable unit-label. When considering sets ofpriceable-unit-labels to combine into a link-label-set, logic is addedto evaluate the reissue methods that are compatible with everypriceable-unit-label. Cross-slice data structures are set up so thatthey keep track of the range of flights from the original ticket thatare reused, and also the range of fare breakpoints from the originalticket that are reused, and different link-label-sets are produced fordifferent values of these ranges. The resulting reissue status vector isstored on the link-label-set.

When performing final linking, the cross-slice summary informationincludes the first flight from the original ticket that was not reused,and the first faring-market of the solution that was not on the originalticket. Different link-fringes are produced for each different value ofthese fields. The final evaluation of many reissue-method conditions,such as “must reuse first coupon,” and “must keep same fare breakpoints”occurs at this stage using the cross-slice summary information. Thefinal reissue status vector for the complete set of solutionsrepresented by a link-fringe is stored in the link-fringe datastructure.

Many aspects of QPX functionality described, for example, in U.S. Pat.No. 6,275,808 can be extended to applications that search for ticketchanges. Examples of these include “sell-up” functionality in which adiverse set of possible pricing solutions are shown for the same ticketchange, including refundable versus nonrefundable options, differentcabin classes, and different fare restrictions. Other QPX functionalityincludes offering split-ticket and multiple point-of-sale options, theuse of calendar queries for allowing comparison shopping over a largenumber of dates, the use of “anywhere” queries for allowing comparisonshopping over a large number of possible new destinations, and changingfrequent-flyer tickets.

The reissue method process 68 described above (see FIG. 5) considers allreissue methods for possible pricings of possible replacementitineraries examining the status vectors over the possible reissuemethods, as generally described above.

A number of embodiments of the invention have been described.Nevertheless, it will be understood that various modifications may bemade without departing from the spirit and scope of the invention.Accordingly, other embodiments are within the scope of the followingclaims.

1. A method for managing changes to a purchased ticket, the methodcomprising: locating a married segment indicator associated with firstand second married flight segments of the purchased ticket; determiningwhether changes to the purchased ticket do not affect existing bookingsof the first and second married flight segments; if the ticket changesdo not affect the existing booking at least one of the first and secondmarried flight segments, constructing a replacement ticket includingchanges to the purchased ticket, the replacement ticket including thefirst and second married flight segments of the purchased ticketutilizing the existing booked inventory; otherwise, if the ticketchanges affect at least one of the first and second married flightsegments, using current availability information for the first andsecond married flight segments from the replacement ticket.
 2. Themethod of claim 1, further comprising: determining that the changesaffect the existing booking of one of the first and second marriedflight segments of the purchased ticket; and discarding a candidatereplacement ticket including the married flight segment, the candidatereplacement ticket including the changes to the purchased ticket.
 3. Themethod of claim 1, further comprising receiving a response to anavailability query associated with the replacement ticket, the responseincluding a married segment indicator associated with the first andsecond married flight segments of the replacement ticket.
 4. The methodof claim 1, wherein the married segment indicator indicates that thefirst and second flight segments held in the passenger name record ofthe purchased ticket are to be considered as one indivisible unit oftravel.
 5. The method of claim 1, wherein the changes affect adestination airport of one of the first and second married flightsegment.
 6. The method of claim 1, further comprising using the firstand second married flight segments from the purchased ticket whenconstructing the replacement ticket if the changes do not affect thefirst and second married flight segments of the purchased ticket.
 7. Asystem for managing changes to a purchased ticket, the systemcomprising: one or more processors configured to: locate a marriedsegment indicator associated with first and second married flightsegments of the purchased ticket; determine whether changes to thepurchased ticket do not affect existing bookings of the first and secondmarried flight segments; if the ticket changes do not affect theexisting booking at least one of the first and second married flightsegments, construct a replacement ticket including changes to thepurchased ticket, the replacement ticket including the first and secondmarried flight segments of the purchased ticket utilizing the existingbooked inventory; otherwise, if the ticket changes affect at least oneof the first and second married flight segments, using currentavailability information for the first and second married flightsegments from the replacement ticket.
 8. The system of claim 7, whereinthe one or more processors are further configured to: determine that thechanges affect the existing booking of one of the first and secondmarried flight segments of the purchased ticket; and discard a candidatereplacement ticket including the married flight segment, the candidatereplacement ticket including the changes to the purchased ticket.
 9. Thesystem of claim 7, wherein the one or more processors are furtherconfigured to: receive a response to an availability query associatedwith the replacement ticket, the response including a married segmentindicator associated with the first and second married flight segmentsof the replacement ticket.
 10. The system of claim 7, wherein themarried segment indicator indicates that the first and second flightsegments held in the passenger name record of the purchased ticket areto be considered as one indivisible unit of travel.
 11. The system ofclaim 7, wherein the changes affect a destination airport of one of thefirst and second married flight segment.
 12. The system of claim 7,wherein the one or more processors are further configured to: use thefirst and second married flight segments from the purchased ticket whenconstructing the replacement ticket if the changes do not affect thefirst and second married flight segments of the purchased ticket.
 13. Acomputer program product for managing changes to a purchased ticket, thecomputer program product being tangibly stored on machine readablemedia, comprising instructions operable to cause one or more processorsto: locate a married segment indicator associated with first and secondmarried flight segments of the purchased ticket; determine whetherchanges to the purchased ticket do not affect existing bookings of thefirst and second married flight segments; if the ticket changes do notaffect the existing booking at least one of the first and second marriedflight segments, construct a replacement ticket including changes to thepurchased ticket, the replacement ticket including the first and secondmarried flight segments of the purchased ticket utilizing the existingbooked inventory; otherwise, if the ticket changes affect at least oneof the first and second married flight segments, use currentavailability information for the first and second married flightsegments from the replacement ticket.
 14. The product of claim 13,further comprising instructions to: determine that the changes affectthe existing booking of one of the first and second married flightsegments of the purchased ticket; and discard a candidate replacementticket including the married flight segment, the candidate replacementticket including the changes to the purchased ticket.
 15. The product ofclaim 13, further comprising instructions to: receive a response to anavailability query associated with the replacement ticket, the responseincluding a married segment indicator associated with the first andsecond married flight segments of the replacement ticket.
 16. Theproduct of claim 13, wherein the married segment indicator indicatesthat the first and second flight segments held in the passenger namerecord of the purchased ticket are to be considered as one indivisibleunit of travel.
 17. The product of claim 13, wherein the changes affecta destination airport of one of the first and second married flightsegment.
 18. The product of claim 13, further comprising instructionsto: use the first and second married flight segments from the purchasedticket when constructing the replacement ticket if the changes do notaffect the first and second married flight segments of the purchasedticket.